Tutorial Exercises Week 4

1. Given the following files in your current directory:

   $ ls
   feb90
   jan12.91
   jan19.91
   jan26.92
   jan5.93
   jun87
   jun88
   jun89
   jul89
   jul93
   mar93
   memo1
   memo10
   memo2
   memo.dat
   $
         

   What would be the output from the following commands?
   1. echo *
   2. echo m[a-df-z]*
   3. echo jan*
   4. echo ?????
   5. echo [jm][au][nr]*
   6. echo *[!0-9]
   7. echo [A-Z]*
   8. echo *.*

2. Which of the following are valid variable names?

   XxXxXx
   12345
   file.name
   file_name
   file1
   _
   HOMEDIR
   _date
   x0-9
   Slimit
         

3. Suppose your HOME directory is /usr/person and that you have subdirectories as shown below:
   
   Assume you have just logged into the system and typed the following commands:

   $ docs=/usr/person/documents
   $ let=$docs/letters
   $ prop=$docs/proposals
   $ prog=/usr/person/programs
         

   Write the commands in terms of these variables to:
   1. List the contents of the documents directory
   2. Copy all files from the letters directory to the proposals directory.
   3. Move all files whose names contain a capital letter from the letters directory to the current directory.
   4. Count the number of files in the memos directory.
   What would be the effect of the following commands?
   1. ls $let/..
   2. cat $prop/sys.A
   3. echo $let/*
   4. cp $let/ask.ALP $prog
   5. cd $prop